1. Field of the Invention
This invention relates to inflation valves for compressed gas cylinders used for inflating inflatable articles such as life rafts. More particularly, this invention relates to inflation valves that utilize the pressure of the gas in the gas cylinder to assist in the opening of the valve to a fully-open position by pulling on an inflation handle.
2. Description of the Background Art
Presently, there exists many types of inflation valves designed to be used in conjunction with compressed gas cylinders or the like. In their simplest forms, inflation valves may comprise a knob or handle which is turned to open a flow passageway allowing the compressed gas within the cylinder to inflate the inflatable article. However, even more prevalent are inflation valves for sealed gas cartridges that are operable by means of a jerk handle and lanyard cord that allow the inflatable article to be quickly inflated by a simple jerking of the handle which forces a pierce pin to fracture the frangible seal of the gas cartridge allowing the compressed gas therein to flow to and inflate the inflatable article.
Due to the large force necessary to fracture the frangible seal of a conventional gas cylinder, more contemporary designs of inflation valves employ a powerful spring which is held in its cocked position by means of a sear. Upon jerking of the jerk handle by the user, the sear is released allowing the powerful spring to very forcibly force the pierce pin through the frangible seal of the gas cartridge.
To eliminate the need for inflators having powerful firing springs held in cocked positions, still more contemporary inflation valves utilize the internal pressure of the gas cylinder to assist in driving the pierce pin fully through an internal frangible seal. A representative inflation system with such a pneumatic assist feature, is disclosed in my U.S. Pat. No. 6,089,403, the disclosure of which is hereby incorporated by reference herein. However, there presently exists a need for pneumatically assisted inflators that are configured in such a manner that virtually all of the components thereof may be manufactured from a high-strength, injectable plastic thereby obviating the need for extensive machining of metal parts and the attendant manufacturing and assembly costs thereof.
Therefore, it is an object of this invention to provide an improvement which overcomes the aforementioned inadequacies of the prior art devices and provides an improvement which is a significant contribution to the advancement of the inflation art.
Another object of this invention is to provide an inflator with pneumatic assist that is configured in such a manner that its component parts may be manufactured from an injectable high-strength plastic material.
Another object of this invention is to provide an inflator with pneumatic assist having an inflator body removable from a valve body such that the valve body may be mounted on the gas cylinder and the gas cylinder filled with compressed gas and then at some later point in time, the inflator body installed thereon.
Another object of this invention is to provide a pneumatically assisted inflator having an inline configuration such that the O-ring seal of the pneumatic piston does not wipe across the exhaust port as taught by my prior patent, U.S. Pat. No. 6,089,403.
The foregoing has outlined some of the pertinent objects of the invention. These objects should be construed to be merely illustrative of some of the more prominent features and applications of the intended invention. Many other beneficial results can be attained by applying the disclosed invention in a different manner or modifying the invention within the scope of the disclosure. Accordingly, other objects and a fuller understanding of the invention may be had by referring to the summary of the invention and the detailed description of the preferred embodiment in addition to the scope of the invention defined by the claims taken in conjunction with the accompanying drawings.